In plastic parts-molding operations, there is a need for sorting the output of the plastic molding machine into at least two separate groups--the first group being the desired plastic molded parts, and the other group being the molding-process plastic by-products (such as those herein referred to as elongated "runners") which are typically recycled for ultimate use as the desired plastic molded parts.
In typical operation, a molded parts-and-runner product emerges from the molding machine, which automatically cycles in a predetermined manner, wherein some of the desired molded parts are caused to be separated from the elongated runners. Typically, a jumbled mixture--of separated, randomly-oriented, desired molded parts and elongated runners--is moved from the molding machine via conveying apparatus for sorting (i.e., for separation into the two groups mentioned immediately above).
The process of sorting the output of molding machines of this type, in the distant past, was almost always performed by hand. Recently, however, certain devices have been provided, and improvements in methods have been made, to eliminate at least some of the need for manual sorting.
Certain devices and methods for segregation of desirable material from undesirable or unacceptable material are disclosed, for example, in U.S. Pat. Nos. 3,651,938; 3,982,632; 4,264,012; 4,451,030; and 4,484,684.
U.S. Pat. Nos. 3,651,938 (to Suellentrop, Jr., et al.) and 3,982,632 (to DeLeon et al.) each discloses a conveyer belt and a cylinder spaced laterally therefrom.
U.S. Pat. No. 4,264,012 (to Paradis) discloses a pair of spaced-apart baffles, and an axially-rotatable coil sandwiched therebetween.
U.S. Pat. No. 4,454,030 (to Young) discloses a conveyer belt that is fed by a screw-equipped conveyer.
U.S. Pat. No. 4,484,684 (to Tetreault) discloses an apparatus comprising a conveyer, a parts separator that is fed by the conveyer, an auger-comminuting device, and a chute. The auger-comminuting device and the chute are spaced from each other and from the parts separator which feeds them both.
Experience has shown that conventional devices, such as those briefly mentioned immediately above, possess certain deficiencies and accordingly present certain problems. For example, some prior-art devices have shown themselves to be less than thorough in their segregation of parts from runners.
In particular, it has been observed, when utilizing such conventional devices or apparatus, that runners (i.e. the undesirable by-products) too frequently fall between members or components that are purportedly intended or designed to catch or hold such runners, with the result being that an unacceptable percentage of the runners tends to be carried along with the separated, desired parts, which is of course undesirable. Such a result may necessitate subsequent manual separation (as was briefly mentioned above), or may result in the jamming of certain downstream equipment that is utilized, for example, to incorporate the desired part into a final product.
In modern factories that produce plastic molded parts, or that use such plastic parts in subsequent assembly, there is a need for an improved segregating apparatus which substantially eliminates or at least tends to minimize the failure of conventional parts-sorting equipment, for acceptably automatically sorting the desired parts from the scrap or by-product parts or pieces.